Emulsifiers



Nov. 28, 1961 E. A. BROW N 3,010,705

. EMULSIFIERS Filed Sept. 26, 1960 INVENTOR IZZan/YZMM 27;

BY wm vh n 'maL 1 wJm.

ATTORNEYS United States Patent Ofifice.

3,010,705 Patented Nov. 28, 1961 3,010,705 EMULSIFIERS Ethan AllanBrown, 75 Bay State Road, Boston 15, Mass. Filed Sept. 26, 1960, Ser.No. 58,436 7 Claims. (Cl. 259-98) This invention relates to emulsifiersand more particularly to an apparatus for forming emulsions suitable foruse in hypodermic injections.

This application is a continuation-in-part of application Serial No.805,014, filed April 8, 1959.

It can be shown that stable water-in-oil emulsions in which the aqueouscomponent contains a therapeutic agent or a toxin are much more slowlyabsorbed by the blood than if the active agent is injected in the formof an aqueous solution, provided the dispersion is sufficiently fine.Thus when a saline solution of a toxin is emulsified in oil with the aidof an emulsifying agent, each globule of the solution is surrounded byoil which must be devoured by the macrophage cells of the blood beforethe solution becomes available. It is therefore possible, byadministering various types of agents in the form of emulsions, toinject at one time a much larger quantity of the agent than wouldotherwise be permissible, the release of the agent being gradual andextending over a substantial period as the result of the slow andprolonged absorption.

It-is therefore the primary object of the invention to provideemulsifying apparatus capable of protecting extremely fine dispersionsof immiscible liquids.

It is another object of this invention to provide an a paratus forforming stable emulsions which may be produced by the simple adaption ofdevices commonly employed in the administering of hypodermic injections,namely, conventional hypodermic syringes and needles. It is a furtherobject of this invention to provide an emulsifying apparatus which canbe adjusted in order to permit variation of the fineness of thedispersion obtained.

With these and other objects in view the preferred practice of thepresent invention contemplates a needle which is standard excepting thatthe usual hub for attachment to the nozzle of the pump barrel secured toboth ends of the needle rather than to one end only. One or both of thehubs are provided with threaded members positioned transversely to thelongitudinal axis of the bore of the hubs and having root diametersgreater than the diameter of the hub bores. The threaded members areadapted to completely occlude the bores of the hubs when turned in totheir innermost positions. After drawing two immiscible liquids into thebarrel of a hypodermic syringe, for instance, an oil and an aqueoussolution of a therapeutic agent, and an emulsifier; the loaded syringeis attached to one hub on the above described needle and an emptysyringe is attached to the hub at the opposite end of the needle. Thethreaded member or members are then turned in to partially occlude thebore of the hub. The mixture of liquids may then be pumped back andforth from one syringe to another through the needle, and the turbulenceimparted to the fluid in passing throughthe restricted bore of the hubrapidly effects an extremely fine dispersion of the aqueous andoleaginous components; the resulting emulsion being excellently adaptedfor injection into human beings or animals with consequent slowabsorption of the active agent. by varying the degree of occlusion ofthe hub bore by the threaded member or members.

Other objects, advantages and novel features of the invention willbecome apparent upon consideration of The fineness of the dispersion maybe controlled the following detailed description, taken in conjunctionwith the accompanying drawing, wherein:

FIGURE 1 is a view in elevation of two hypodermic syringes connected bya needle having a hub on each end for attachment to the respectivenozzles of the syringes.

FIGURE 2 is a perspective view of the needle and hubs before assemblywith the syringes, and

FIGURE 3 is a longitudinal sectional view taken on the line 3 3 ofFIGURE 1 and illustrating the threaded member utilized to occlude partof the hub bore.

In the following description, reference is made to the embodimentthereof illustrated in the accompanying drawing, and specific languageis employed. Nevertheless it will be appreciated that no limitation ofthe scope of the invention is thereby intended, such furthermodifications and alterations of the illustrated structure as wouldnormally occur to one skilled in the art being contemplated.

The hypodermic syringes illustrated in FIGURE 1 are entirelyconventional, each comprising a barrel 10 having a nozzle 11 at thedischarge end thereof, and a plunger 12 fitted within the barrel. Thenozzles 11 are tapered slightly toward the discharge outlet, and eachnozzle is dimensioned to receive thereon a conventional needle hub 15,the hub being retained on the nozzle by friction. The barrel of eachsyringe, including the nozzle, and the plunger may be made of glass; thehubs 15 are commonly formed of metal, and their retention on the nozzlesmay be assured by heating the hubs prior to their application, pressingthem tightly on the nozzle, and allowing them to cool, whereby thenozzles are tightly gripped by the hubs. Alternatively, retention of thehubs in assembled relation with the nozzles may be assured by theprovision on each nozzle of a locking sleeve having cam surfaces orthreads therein which are engaged by the hub flange 16, as in theconventional Luer-Lok type of hub, illustrated in the patent toDickinson 1,742,497, granted January 7, 1930. It will be appreciatedthat the detailed structure of the syringes and the hub thus fardescribed form no part of the instant invention and may vary widely fromthat illustrated.

The hubs 15 are soldered, brazed, welded or otherwise permanentlysecured to opposite ends of a needle or tube 20; the needle having abore ranging from about 10 gauge to 15 gauge. The tube 20 need notnecessarily be a hypodermic needle as any similar metal tube willsuffice. Furthermore, the internal diameter of the needle ortube 20 isnot particularly critical in the present invention and any tube may beutilized which will conveniently couple together the hubs 15. It is onlynecessary that the internal diameter of the needle or tube 20 be nosmaller than the diameter of a central bore 21 provided in each of thehubs 15.

,Each hub 15 is provided with a threaded member or set screw 22transversely disposed with respect to the bores 21 and adapted tointersect the bores 21 when turned in. The bores 21 are provided withsockets 23'which serve as seats for theends of the set screws 22 whenthe set screws have been turned all the way in. p The root diameter ofset screws 22 is selected to'be somewhat greater than the diameter orgauge of the needle 20 and bores- 21. Since the axes of the bores 21 andset screws 22 intersect at right angles when the set screws 22 have beenturned down until the inner extremities thereofseat .in sockets'23, thebores 21 will be completelyioccluded by thesetscrws22; i j, 1 In thepractice of; my inventionlfirst draw the aqueous and oleaginous fluidsinto one of the syringes 10, preferably using a blunt pointed needle of13 gauge or larger bore, so that the liquids may readily be drawn insuccession into the syringe. The materials which are to be emulsifiedmay, of course, vary widely. By way of Arlacel A.

After the first syringe has been charged, the needle used in filling thesame is removed and a needle having hubs attached at opposite ends isfitted to the filled syringe and to an empty syringe as shown in FIGURE1, so that the needle provides a capillary tube connecting the twosyringes. The set screws 22 are then turned in to partially occlude thebores 21 to the extent necessary to produce the desired fineness ofdispersion. For this purpose it may be desirable to calibrate set screws22 in order that the desired dispersions may be obtained. The set screwscould, for example, be calibrated in microns or any other suitableunits. In order to insure accurate control of the fineness of thedispersion obtained it is necessary that the threads on the set screws22 be made quite fine.-

The mixture of fluids is then discharged from one. syringe into theother repeatedly by alternate pumping of the syringes. The excessiveturbulence imparted to the fluids in passing to and fro through theopenings defined by the bores 21 and the inner extremities of the setscrews 22 breaks them down rapidly into exceedingly V fine particles,thus facilitating the formation'of a fine dispersion. The double endedneedle and the empty syringe may then be withdrawn, and the loadedsyringe supplied with the conventional needle for 'the purpose ofinjecting the resulting stable emulsion, with the beneficial efle'ctshereinbefo're mentioned.

Although the present invention has been described as utilizing a setscrew in each of the hubs 15, it is, of course, obvious that only oneset screw need be provided. It is, however, advantageous to utilize aset screw in each of the hubs 15 since this arrangement provides twopoints of turbulence for the fluids during each pass from one syringe tothe other. Also, it may be desirable in some instances to utilize aneedle 20 having a relatively small bore (for example, 16 gauge to 22gauge) to create .still more turbulence in the moving fluids and =1. .Anemulsifier comprising a pair of hypodermic syringes, a hub fitted to thenozzle of each syringe, each.

of said hubs being provided with a central bore coaxial with saidnozzles, a tube interconnecting said hubs and coaxial with'said bores toprovide a continuous uninterrupted fluid passageway f-unif0rmcross-section be-' tween said syringes, and adjustablemeans forpartially occluding at'least one-of said central bores.

2. An emulsifier as defined in claim 1 wherein said adjustable means isa threaded member disposed in a threaded aperture transverse to the axisof said central bore.

hyringes, a hypodermic needle, a hub secured to each end'of said'needle,each ,hub being provided with a central bore'coaxial with said needle,each hub being :fit

ted to the nozzl'e'of one'of said syringes to provide a continuousuninterrupted fluid passageway of umform tcrosss'ection between saidsyringes, and adjustable means for partiallygoccluding the central boreof at least one 3. A device for use in forming emulsions for hypodermicinjection comprising a pair of hypodermic 4 of said hubs, whereby twoimmiscible liquids drawn into one of said syringes prior to fitting sameto its hub may be pumped repeatedly from one to the other of saidsyringes through said needle and said partially occluded bore to form anemulsion of the liquids.

4. A device for use in forming emulsions for hypodermic injectioncomprising a pair of hypodermic prior to fitting the same to its hub maybe pumped repeatedly from each of said syringes into the other 'of saidsyringes through said needle and said partially occluded bore toemulsify the aqueous and oleaginous components.

5. A device for use in forming emulsions for hypodermic injection,comprising a pair of hypodermic syringes, a hypodermic needle of about16 gauge to about 22 gauge, and a hub secured to each end of 'saidneedle, each hub being fitted to the nozzle of one of said syringes toprovide a continuous uninterrupted fluid passage 'way of uniformcross-section between said syringes,

whereby two immiscible liquids drawn into one of said syringes prior tofitting the same to its hub may be pumped repeatedly from one to theother of said syringes through said needle to form an emulsion of theliquids.

6. A device for use in forming emulsions f'or hypodermic injection,comprising a pair of hypodermic syringes, a capillary tube of about 16gauge to about 22 gauge, and a hub secured to each end of said tube,each hub being fitted to the nozzleof one of said syringes to provide acontinuous uninterrupted fluid passageway of uniform cross-sectionbetween said syringes, whereby a aqueous medium, an oil, and anemulsifier drawn'into one of said syringes prior to fitting the same toits hub may be pumped repeatedly from each of said syringes into thesyringes, a hypodermic needle, and 'a hub secured to each end of saidneedle, each hub being 'fitted to the nozzle of one of said syringes toprovide a continuous uninterrupted fluid passageway of uniformcross-section between an emulsifier drawn into one of said syringesprior-to fitting the same to its hub may be pumped repeatedly into theother of said syringes through said needle and repeatedly returned tothe first of said syringes through said needle to ,emulsify the aqueousand oleaginous components.

References Cited in the file of this "patent UNITED srA'rnsl PATENTS V I2,026,604 Altreds Jan. 7, 1936 2,124,580 Laviue "July 26, 1938 2,158,593Scrimgeour- --May .16, 1939 2,172,661 Krauss Sept. 12, 1939 2,410,546McCabe' Nov.'5, 1946 2,477,598 Hain Aug. 2, 1949 2,726,656 Lockhart Dec,13., 1955

